. Handbook of nature-study for teachers and parents, based on the Cornell nature-study leaflets. Nature study. Earth Study 847. Sand. Clay. Loam. The water has nearly reached the upper surface of the sand and is halfway up the loam; in the clay it has climbed but a short distance. Experiment j—To show that soil lifts water upfront below—Use the same soils arranged in the same way as for Experiment i, but instead of pouring water in at the top, place the three lamp chimneys in a pan which has water in it about an inch deep. In which soil does the water rise most rapidly ? In which does it rise
. Handbook of nature-study for teachers and parents, based on the Cornell nature-study leaflets. Nature study. Earth Study 847. Sand. Clay. Loam. The water has nearly reached the upper surface of the sand and is halfway up the loam; in the clay it has climbed but a short distance. Experiment j—To show that soil lifts water upfront below—Use the same soils arranged in the same way as for Experiment i, but instead of pouring water in at the top, place the three lamp chimneys in a pan which has water in it about an inch deep. In which soil does the water rise most rapidly ? In which does it rise the highest? After the water has been taken up, let the soil stand in the lamp chimneys for several days. Which soil dries out the soonest? If we had three fields, one of loam, one of clay, and one of sand, in which would the most water be lifted from below for the use of the plants? Which would retain the water longest ? Hints for teacher on Experiment j •—Water rises through the sand in a short time; if rather fine sand is used it requires less than half an hour. To rise through loam it will require three or four times as long, and may not reach the top of the clay for several days. If the glass tubes were three or four feet long and allowed to stand for several days, we would find that although the water climbs very slowly through the clay it will climb to a greater height in clay than in loam or sand. Under field conditions clay will retain moisture for a longer time than sand or loam. Experiment 4—To show that mulch keeps the water from evaporating from soils—Take two of the lamp chimneys filled half full with loam. Pour in the same amount of water in each until the soil is thoroughly wet. Cover the top of one with an inch deep of dry, loose earth. Which dries out first? What does the loosening and pulverizing of the soil in our fields by harrowing do for our planted crops ? What is a mulch ? Hints for teacher on Experi- ment 4—The soil covered with a layer o
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